“Sure, Tuppence, how could he be? This door’s open into the hall. No one could have come in by the front door without our seeing and hearing him.”

“I can’t help it. I feel he’s here!”

She looked appealingly at Sir James, who replied gravely:

“With due deference to your feelings, Miss Tuppence (and mine as well for that matter), I do not see how it is humanly possible for anyone to be in the flat without our knowledge.”

The girl was a little comforted by his words.

“Sitting up at night is always rather jumpy,” she confessed.

“Yes,” said Sir James. “We are in the condition of people holding a séance. Perhaps if a medium were present we might get some marvellous results.”

“Do you believe in spiritualism?” asked Tuppence, opening her eyes wide.

The lawyer shrugged his shoulders.

“There is some truth in it, without a doubt. But most of the testimony would not pass muster in the witness-box.”